Changeset 3066 for trunk/sources/HeuristicLab.Problems.TSP/3.3/Evaluators/TSPCoordinatesPathEvaluator.cs

Timestamp:

03/16/10 16:04:54 (14 years ago)

Author:

swagner

Message:

Implemented first version of distance matrix-based evaluation for the TSP (#912)

File:

• trunk/sources/HeuristicLab.Problems.TSP/3.3/Evaluators/TSPCoordinatesPathEvaluator.cs (modified) (2 diffs)

trunk/sources/HeuristicLab.Problems.TSP/3.3/Evaluators/TSPCoordinatesPathEvaluator.cs

@@ -39 +39 @@
       get { return (ILookupParameter<DoubleMatrix>)Parameters["Coordinates"]; }
     }
+    public ILookupParameter<DoubleMatrix> DistanceMatrixParameter {
+      get { return (ILookupParameter<DoubleMatrix>)Parameters["DistanceMatrix"]; }
+    }
+    public ILookupParameter<BoolValue> UseDistanceMatrixParameter {
+      get { return (ILookupParameter<BoolValue>)Parameters["UseDistanceMatrix"]; }
+    }
 
     protected TSPCoordinatesPathEvaluator()
@@ -44 +50 @@
       Parameters.Add(new LookupParameter<Permutation>("Permutation", "The TSP solution given in path representation which should be evaluated."));
       Parameters.Add(new LookupParameter<DoubleMatrix>("Coordinates", "The x- and y-Coordinates of the cities."));
+      Parameters.Add(new LookupParameter<DoubleMatrix>("DistanceMatrix", "The matrix which contains the distances between the cities."));
+      Parameters.Add(new LookupParameter<BoolValue>("UseDistanceMatrix", "True if a distance matrix should be calculated and used for evaluation, otherwise false."));
     }
 
     public sealed override IOperation Apply() {
-      Permutation p = PermutationParameter.ActualValue;
-      DoubleMatrix c = CoordinatesParameter.ActualValue;
+      if (UseDistanceMatrixParameter.ActualValue.Value) {
+        Permutation p = PermutationParameter.ActualValue;
+        DoubleMatrix dm = DistanceMatrixParameter.ActualValue;
 
-      double length = 0;
-      for (int i = 0; i < p.Length - 1; i++)
-        length += CalculateDistance(c[p[i], 0], c[p[i], 1], c[p[i + 1], 0], c[p[i + 1], 1]);
-      length += CalculateDistance(c[p[p.Length - 1], 0], c[p[p.Length - 1], 1], c[p[0], 0], c[p[0], 1]);
-      QualityParameter.ActualValue = new DoubleValue(length);
+        if (dm == null) {  // calculate distance matrix
+          DoubleMatrix c = CoordinatesParameter.ActualValue;
 
+          dm = new DoubleMatrix(c.Rows, c.Rows);
+          for (int i = 0; i < dm.Rows; i++) {
+            for (int j = 0; j < dm.Columns; j++)
+              dm[i, j] = CalculateDistance(c[i, 0], c[i, 1], c[j, 0], c[j, 1]);
+          }
+          DistanceMatrixParameter.ActualValue = dm;
+        }
+
+        double length = 0;
+        for (int i = 0; i < p.Length - 1; i++)
+          length += dm[p[i], p[i + 1]];
+        length += dm[p[p.Length - 1], p[0]];
+        QualityParameter.ActualValue = new DoubleValue(length);
+      } else {
+        Permutation p = PermutationParameter.ActualValue;
+        DoubleMatrix c = CoordinatesParameter.ActualValue;
+
+        double length = 0;
+        for (int i = 0; i < p.Length - 1; i++)
+          length += CalculateDistance(c[p[i], 0], c[p[i], 1], c[p[i + 1], 0], c[p[i + 1], 1]);
+        length += CalculateDistance(c[p[p.Length - 1], 0], c[p[p.Length - 1], 1], c[p[0], 0], c[p[0], 1]);
+        QualityParameter.ActualValue = new DoubleValue(length);
+      }
       return base.Apply();
     }